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Microsoft has released the Developer Preview of the Windows Phone 8.1 release. Windows Phone 8 was a minor upgrade from the consumer point of view, but it was huge in that Microsoft has changed the Windows Phone kernel from Windows CE to the real Windows NT. That meant the future upgrades could be installed on older phones, but also meant that Windows Phone 7 is no longer compatible and also that Windows Phone 8 is barely an update. More like a point-one increase.
Now, Windows Phone 8.1 is a much different OS, considered by many to be Windows Phone 9 or similar, but Microsoft choose to call it 8.1 to align it with the Desktop version (even though Windows 8.1 got the Windows 8.1 Update).
I have installed Windows Phone 8.1 two days ago, the exact moment it was available (the phone notified me, and I was already a registered developer). The installation didn't go smoothly, the phone (Lumia 720) got stuck on the Gears screen and I had to hard-reset it and then to reinstall the OS with the Nokia Software Recovery tool. After that I once again did the developer unlock, installed the App and ran the update. This time it finished but all my data and apps were corrupted. I had to update most of them through the Windows Store and there was a problem...
THE USB DIDN'T WORK ANY MORE! Also the Camera app caused the phone to freeze, show a black screen and reboot. Sometimes it would get stuck in the reboot- loop and I had to soft-reset it. Also most of my Nokia-exclusive apps disappeared, which is bad considering I really liked Nokia Music.
The OS review
The notifications center ("Action Center")
This was one of the coolest Windows Phone 8.1 features (other than Cortana, of course). I really hated that you couldn't see the history of the notifications, so it's my favourite feature. Also it has the quick-toggles which are customizable (Android and iOS, take note!). One bad thing is that the Music app didn't show in the notifications like on Android (but it's still on the volume settings pull-down).
The Volume settings
On Windows Phone 8 you only had the global, hardware button controlled, volume setting. Now, not only you have a quick mute and vibration toggle, but also a slider for Ringer and Multimedia volumes. Android already had this, but it depends on where you are (decreasing or increasing the volume in the Dialer app changed the Multimedia volume, but on the Home screen it changed the Ringer volume).
The Swipe keyboard
This is another cool feature of Windows Phone 8.1, as I really liked the Swipe-styled (not actually Swipe, but instead the Touchpal Plus) keyboard. The Windows Phone 8.1 Swipe keyboard is not that good, probably because it needs some improvement, but still it's much faster than manually pressing all buttons (although Windows Phone's keyboard is in my opinion better than the stock Android keyboard, at least in typing)
Data and Storage senses (also Battery Saver)
Storage Sense is really useful as it enables you to see which apps are using the most space on your phone's memory. Data Sense can turn on Data-saving features like page compression and image compression. It'll make web pages load faster in IE and also save you a lot of data. Now you don't need to use the Nokia Xpress browser. Battery Saver was always in the phone, but now it's much more visible and it does the same thing: turn on the battery-saving features.
Wi-Fi sense is another partially-new feature that can share your networks' credentials with your friends so you don't need to tell them your password when they come over. It can also auto-fill in all the data on some Wi-Fi networks that require you to register on a portal to actually use them.
A new Music, Photos, Camera, Videos and Podcasts apps
First of all, the Camera was apparently made better, but in my case it ten times worse as I can't even open it without my phone rebooting. Music and Videos are now separate and are called Xbox Music and Xbox Videos, but somewhere Music and Videos. There's a new Podcasts app that I can't use since I'm not in the U.S.
The new Photos app removes the screen where you needed to select Photos, Albums, etc., but also removed the option to have the background of the app be a picture from your Favourites album. I actually welcome this change, since I hated having my horrible pictures stretched out over the app.
A new Store
The Windows Store was overhauled. It's now promoting apps that were buried in other menus before. It also has a new History screen, and also My Apps which aren't installed but were sometime in the past and can be reinstalled in bulk or one-by-one.
Again, it's not that much better for me, since most of the good features are US-only. I also have a "Telenor Recommended apps" screen which ruins the experience completely (Telenor is my carrier).
A better Browser
Internet Explorer 11 is the new Browser for Windows Phone 8.1. It has a new Reading View (similar to my project read, and also Readability).
The new Browser also has a stop/refresh button in the URL bar and the old, customizable, button that can be either Tabs or Favourites.
It also finally removed the border around linked images, so Gmail now looks normal (even though Google is evil and doesn't allow Windows Phone to have the new, AJAX-powered, Gmail interface)
Internet Explorer 11 now has unlimited tabs, and doesn't delete them after you close it, and it can also sync tabs to Windows 8.1 Internet Explorer. It's also up to 20% faster than previous versions.
The new 3-width Start screen
Now all phones, not only those with bigger screens (like Lumia 1520), get the 3-tile wide screen. I personally don't like it that much, as I have a different layout than most other Windows Phone users, but I'm sure many people asked for it.
Since Windows 8.1 Update supports Silverlight APIs for Windows Phone 7 and 8 and also Xbox APIs, and Windows Phone 8.1 support WinRT APIs (that Windows 8.1 also supports) and Xbox APIs and Xbox One supports WinRT and Silverlight APIs [...] there's now a Universal App.
Universal Apps are apps that you buy on one device (say a Microsoft Surface) and they are available on your Windows Phone, Xbox and your Desktop. It's actually a really good system, much better than Apple's (iOS apps can't run on OS X).
Other minor changes
The People hub now supports external applications, but is also de-integrated with Facebook. You can't upload photos manually to SkyDrive (now OneDrive). There's support for VPNs. "Assigned Access" or Kiosk mode is also available. Many apps are broken. There's support for WinRT APIs alongside Silverlight 8.1 and 8. Windows Phone 8.1 also supports on-screen buttons for Start, Back and Search, so manufacturers can use existing designs for Android with Windows Phone 8.1. The only requirement is a hardware power button and a volume rocker.
Last but not least, the most amazing Windows Phone 8.1 feature... will not be in this review because it doesn't work outside of the US. And even if I switch the Region of the phone, it still can't understand anything because of my accent.
I hope you liked the review, as always you _can't _comment on it, but if you found a mistake, contact me on my Contact page or on Social networks (that I don't have profiles on, lol)
This post was last updated on February 16th, 2020.